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==Suitable conditions==
* Infiltration galleries are often installed in shallow or fine sediment beds where there is poor permeability or lack of sand depth – in this case, the length proves to be advantageous.
* They can also be sited in areas where riverbanks are too high to allow manual or motorized suction pumps to operate.
- Can clog up over time
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==Resilience to changes in the environment==
====Drought====
'''Effects of drought''': Can dry up.
'''Underlying causes of effects''': Less recharge of aquifer due to less rainfall; Increasing population & water demand; Size of aquifers – e.g. limited sand volume; Wells not sunk deep enough into water table; Incorrect siting; Graded gravel around pipe not correctly done
'''To increase resiliency of WASH system''': Increase volume through construction of groundwater dam; Sink wells/pipes deeper; De-water wells during caissoning within the water table; Construct during the latter half of the dry season; Site in riverbeds that are dry for part of the year, where water remains in the riverbed throughout the dry season; Increase flow by use of porous concrete & perforated pointed steel pipes driven horizontally into the aquifer (riverbed wells) and graded gravel (infiltration galleries & jetted wells); Site in a degrading river section where there is no deposition (infiltration galleries); Put graded gravel around pipes to minimize clogging and increase flow.
==Construction, operations and maintenance==
'''General advice on cement''': A common cause of cracks in structures and linings (e.g. in tanks, dams, waterways, wells) is errors in mixing and applying the cement. First of all, it is important that only pure ingredients are used: clean water, clean sand, clean rocks. The materials have to be mixed very thoroughly. Secondly, the amount of water during mixing needs to minimal: the concrete or cement needs to be just workable, on the dry side even, and not fluid. Thirdly, it is essential that during curing the cement or concrete is kept moist at all times, for at least a week. Structures should be covered with plastic, large leaves or other materials during the curing period, and kept wet regularly.
[[Image:InfiltrationGalleryDiagram.jpg|thumb|right|300px|Infiltration gallery. <br> Drawing: © Ken Chatterton. In: Hussey, S.W. (2007) Water from sand rivers: guidelines for abstraction. WEDC, Loughborough University, UK.]]
[[Image:InfiltrationGalleryBuild.jpg|thumb|right|300px|Building an infiltration gallery. Infiltration Area: 1080 ft2 (100.3 m2). Cost - $9.33/foot2. Overseas supplier (AUS).]]
